The present invention relates to a ferroelectric film, a method of manufacturing a ferroelectric film, a ferroelectric capacitor, a method of manufacturing a ferroelectric capacitor, and a ferroelectric memory.
As a ferroelectric film applied to semiconductor devices (ferroelectric memory (FeRAM), for example), a ferroelectric film having a perovskite structure (PbZrTiO, for example) and a ferroelectric film having a layered perovskite structure (BiLaTiO, BiTiO, or SrBiTaO, for example) have been proposed.
Pb or Bi contained in the material for the ferroelectric film easily volatilizes at low temperature due to high vapor pressure. Since a high-temperature heat treatment is performed during the crystallization process of the ferroelectric film, Pb or Bi bonds to oxygen in the atmosphere necessary for crystallization of the ferroelectric and is released, thereby adversely affecting the characteristics of the crystallized ferroelectric film.
In recent years, the degree of miniaturization and integration of the semiconductor device has been increased. Therefore, a reduction of the thickness of the ferroelectric film has been demanded. However, it is difficult to form a thin ferroelectric film having excellent characteristics by using conventional manufacturing steps.